How the heck would we know...10.9 hasn't been releaed yet. Besides...if the new MBA gets 11-13 hours with 10.8...how many more hours do you want??

- Nick

- Too many "beachballs", read this: Beachballs- Computer seems slower than it used to? Read this for some slow computer tips: Speedup- Almost full hard drive? Some solutions. Out of Space- Apple Battery Info. Battery

If the new MBA's are doing what the marketing slides claim they can with battery life on Mountain Lion, with then new features of App Nap and other aspects of Mavericks, it is conceivable that it might do better..

If the new MBA's are doing what the marketing slides claim they can with battery life on Mountain Lion, with then new features of App Nap and other aspects of Mavericks, it is conceivable that it might do better..

Oh I'm happy with the 12 hours, I'm just intrigued that it could go even further

Ohh...I agree. When it comes to laptop battery runtime on a single charge...more is better. But very little info is available about OS 10.9...so it's really very early to be asking these questions. At this point...almost any answer you get will be speculation.

Also realize that...as battery runtime get's longer...Apple will most likely be tempted to redesign the battery in the MBA...making it smaller with less capacity (back to 8-10 hours). Since I think that Apple's #1 goal with the MBA is thinness & lightness. And a redesigned battery would/could be both smaller/thinner & lighter.

- Nick

- Too many "beachballs", read this: Beachballs- Computer seems slower than it used to? Read this for some slow computer tips: Speedup- Almost full hard drive? Some solutions. Out of Space- Apple Battery Info. Battery

1. When most battery estimates are made you need to know the conditions under which those tests were made. Small changes in the test procedure (such as screen brightness) can affect the results.

2. Macericks should improve battery life but not all OS upgrades have done so for all users. I seems to remember having this discussion in the chat room shortly after eith Lion or Mountain Lion was released.

I don't know if we'll see an improvement in battery life with OS X Mavericks. The reason the latest MBA gets the battery life that it does is because of the new Intel Haswell low power chipset designed specifically for notebook computers. That plus the newer battery design by Apple have resulted in longer run times.

You're also going to see extended battery life in Windows notebook computers that likewise use the new Haswell chipset. Lower power = less juice for the use!

Actually ... tests of the first few Haswell-based notebooks that we've seen don't show as much improvement in battery time as the MacBook Air. Nine-10 hours is very impressive too, but it's not the 12-15 hour battery life we've seen in MacBook Air reviews ...

1. When most battery estimates are made you need to know the conditions under which those tests were made. Small changes in the test procedure (such as screen brightness) can affect the results.

2. Macericks should improve battery life but not all OS upgrades have done so for all users. I seems to remember having this discussion in the chat room shortly after eith Lion or Mountain Lion was released.

This is very true - in actual useful life, I get less than half what the 'My incredible (insert Mac here) goes for x hours!" usefulness-no-object hypermilers do, and about two-thirds of what the Mac-optimised tests run by many magazines do.

Mac runtime is traditionally very good in very specific areas - media playback (but only with Apple-sanctioned codecs), idle (this is really useful, yeah) and other modes which aren't necessarily condusive to general-purpose productivity.

Generally speaking in actual productivity use with extensive power saving, I get Apple claim / 1.4 - which actually ranks among the lowest for me in terms of manufacturer claim vs real life. With Sony and Lenovo for example I can consistently hit the claimed runtime in productivity use, though again with extensive power saving.

Also, forgot to add to my last post ... the efficiency features in OS X Mavericks *should* result in some further improvement, but it will depend heavily on how the users uses the machine -- so as the saying goes "your mileage may vary" and that's probably why Apple haven't talked about it a lot.